<?php
namespace app\common\model;

use think\Model;
use think\Db;

/**
 * Created by liuyang.
 * Class Tool
 * @package app\common\model
 */
class Tool
{

    //排序
	protected function Array_sort($arr, $keys, $type = 'desc')
	{
		$keysvalue = $new_array = array();
		if (count($arr) == 0) return false;
		foreach ($arr as $k => $v) {
			$keysvalue[$k] = $v[$keys];
		}
		if ($type == 'asc') {
			asort($keysvalue);
		} else {
			arsort($keysvalue);
		}
		reset($keysvalue);
		foreach ($keysvalue as $k => $v) {
			$new_array[$k] = $arr[$k];
		}
		return $new_array;
	}
 
    //加密,解密函数 
	public function bhmd5($string, $operation = 'DECODE', $key = '', $expiry = 0)
	{
		if (is_array($string)) $string = json_encode($string);
		$ckey_length = 4;
		$key = ($key == '') ? md5(config('salt')) : md5($key);

		$keya = md5(substr($key, 0, 16));
		$keyb = md5(substr($key, 16, 16));
		if ($operation != 'ENCODE') {
			$string = str_replace('*-*', '+', $string);
			$string = str_replace('*_*', '/', $string);
		}
		$keyc = $ckey_length ? ($operation == 'DECODE' ? substr($string, 0, $ckey_length) : substr(md5(microtime()), -$ckey_length)) : '';
		$cryptkey = $keya . md5($keya . $keyc);
		$key_length = strlen($cryptkey);
		$string = $operation == 'DECODE' ? base64_decode(substr($string, $ckey_length)) : sprintf('%010d', $expiry ? $expiry + time() : 0) . substr(md5($string . $keyb), 0, 16) . $string;
		$string_length = strlen($string);
		$result = '';
		$box = range(0, 255);
		$rndkey = array();
		for ($i = 0; $i <= 255; $i++) {
			$rndkey[$i] = ord($cryptkey[$i % $key_length]);
		}
		for ($j = $i = 0; $i < 256; $i++) {
			$j = ($j + $box[$i] + $rndkey[$i]) % 256;
			$tmp = $box[$i];
			$box[$i] = $box[$j];
			$box[$j] = $tmp;
		}
		for ($a = $j = $i = 0; $i < $string_length; $i++) {
			$a = ($a + 1) % 256;
			$j = ($j + $box[$a]) % 256;
			$tmp = $box[$a];
			$box[$a] = $box[$j];
			$box[$j] = $tmp;
			$result .= chr(ord($string[$i]) ^ ($box[($box[$a] + $box[$j]) % 256]));
		}
		if ($operation == 'DECODE') {
			if ((substr($result, 0, 10) == 0 || substr($result, 0, 10) - time() > 0) && substr($result, 10, 16) == substr(md5(substr($result, 26) . $keyb), 0, 16)) {
				return substr($result, 26);
			} else {
				return '';
			}
		} else {
			$string = $keyc . str_replace('=', '', base64_encode($result));
			$string = str_replace('+', '*-*', $string);
			$string = str_replace('/', '*_*', $string);
			return $string;
		}
	}

}
